Determination of tamsulosin in human aqueous humor and serum by liquid chromatography–electrospray ionization tandem mass spectrometry

• Published in: Journal of pharmaceutical and biomedical analysis 2007-01, Vol.43 (2), p.606-612
• Main Authors: Keski-Rahkonen, Pekka, Pärssinen, Olavi, Leppänen, Esa, Mauriala, Timo, Lehtonen, Marko, Auriola, Seppo
• Format: Article
• Language: English
• Subjects: Adrenergic alpha-Antagonists - blood; Adrenergic alpha-Antagonists - pharmacokinetics; Analysis; Analytical, structural and metabolic biochemistry; Aqueous humor; Aqueous Humor - metabolism; Biological and medical sciences; Cataract - blood; Cataract - metabolism; Chromatography, High Pressure Liquid - methods; Chromatography, High Pressure Liquid - standards; Fundamental and applied biological sciences. Psychology; General pharmacology; Humans; Intraoperative floppy iris syndrome; LC–MS/MS; Medical sciences; Pharmacology. Drug treatments; Reproducibility of Results; Sensitivity and Specificity; Serum; Spectrometry, Mass, Electrospray Ionization - methods; Spectrometry, Mass, Electrospray Ionization - standards; Sulfonamides - blood; Sulfonamides - pharmacokinetics; Tamsulosin; Tandem Mass Spectrometry - methods; Tandem Mass Spectrometry - standards
• ISSN: 0731-7085; 1873-264X
• DOI: 10.1016/j.jpba.2006.07.016

A simple, sensitive and selective LC–MS/MS method was developed for the determination of tamsulosin in human aqueous humor and serum to study the recently reported eye-related adverse effects of this α 1-blocker drug. Aqueous humor samples were analyzed by direct injection, after addition of the internal standard, labetalol. Liquid–liquid extraction with ethyl acetate was used for serum sample preparation. The chromatographic separation was performed on a reversed phase column by gradient elution with acetonitrile −0.1% formic acid at a flow-rate of 0.2 ml/min. Detection and quantification of the analytes were carried out with a linear ion trap mass spectrometer, using positive electrospray ionization (ESI) and multiple reaction monitoring (MRM). The limit of quantification was 0.1 ng/ml for both aqueous humor and serum samples and linearity was obtained over the concentration ranges of 0.1–4.7 ng/ml and 0.1–19.3 ng/ml for aqueous humor and serum samples, respectively. Acceptable accuracy and precision were obtained for concentrations within the standard curve ranges. The method has been used for the determination of tamsulosin in aqueous humor and serum samples from patients that were on tamsulosin medication and underwent cataract surgery.